1. Field of the Invention
The invention relates to communication of images and, more particularly, to telepresence, including remote video monitoring.
2. Discussion of Related Art
Remote monitoring systems are known to include remotely located video cameras positioned for monitoring from a remote site with a personal computer or display. Such can be connected by any kind of connection such as point-to-point with a telephone line, via the internet or through an internet hub. A video server is used to capture successive real time images from a video camera, digitize and compress them and transfer them frame-by-frame through the internet, intranet or point-to-point protocol direct dial-in connection.
Telepresence is similar in concept to “virtual reality” except images and other stimuli are provided to the user via a connection in a telecommunications network. One approach uses a teleoperated camera platform coupled to the head movements of a remote user wearing a head-tracked, head-mounted display (HTHMD). See U.S. Pat. No. 5,436,638 at column 1, lines 43–48 and column 3, lines 10–31. Instead of a HTHMD, a desktop display can be yoked to the movements of a user seated before the display such as shown in FIGS. 13, 14A, 14B and 16 of U.S. Pat. No. 5,436,638. See also the PUSH desktop display and the BOOM3C head-coupled stereoscopic display, either hand-guided or hands-free (head-guided), of Fakespace, Inc., Menlo Park, Calif. Another approach is to use a remote reality engine with prerecorded scenarios for selection over the network according to monitored movements of the user.
Due to the limited bandwidth typically available for such connections, the rate of frame delivery is very slow and therefore there is a noticeable lag between the time of image capture or retrieval and display. Moreover, the amount of video information conveyed is rather limited since the technology is based on the existing NTSC infrastructure. Consequently, the above described applications for telepresence tend to be lacking in the “presence” aspect and likewise remote viewing tends to be confined to rather static, e.g., industrial plant process monitoring, employee parking lot monitoring, security monitoring for plant ingress/egress, and the like.
However, various competing transport technologies are now being deployed to increase the bandwidth enormously and thereby speed up such connections. These include optical fiber networks, cable, satellite, and techniques to utilize the existing telephony infrastructure of twisted copper pairs as digital subscriber lines. Included in the services deliverable on the links provided according to such technologies will be HDTV. While the bandwidth of such links now being deployed to subscribers can be heavily proportioned in the downstream direction, they also provide at least a significant amount of upstream bandwidth. As a result, there will now be new opportunities for far more dynamic types of telepresence applications, including remote video monitoring, particularly on the Internet, and in ways heretofore never even contemplated. In particular, it can be foreseen that there will be extremely high demand for exciting, new telepresence applications.
Unfortunately, these telepresence applications suffer from an underlying assumption borrowed from the art of “virtual reality” where the user is enabled to navigate within a virtual environment in a highly autonomous manner. The user takes command of the virtual environment and actively controls all of the responses of the reality engine according to monitored activity of the user. This dedication to a single user of the tools needed to generate the virtual environment makes the reality engine unavailable to all but this one user at a given time. A similar situation exists for a remotely located video camera. Since these tools are quite expensive, the cost of use for the single user is high. Hence the anticipated demand cannot be efficiently and economically met.